[Extractor] Handle non-valid json as an operation sample without throwing an exception (#328)

* Handle non-valid json as an operation sample without throwing an exception.

* Extractor: when checking if we need to arm escape the sample response we need to check if content type contains application/json, not equals since it can contain charset information and other things.

Author: bremnes

src/APIM_ARMTemplate/apimtemplate/Extractor/EntityExtractors/APIExtractor.cs

@@ -1,10 +1,11 @@
 using System;
+using System.Collections.Generic;
+using System.Linq;
 using System.Threading.Tasks;
+using apimtemplate.Extractor.Utilities;
 using Microsoft.Azure.Management.ApiManagement.ArmTemplates.Common;
-using System.Collections.Generic;
-using Newtonsoft.Json.Linq;
 using Newtonsoft.Json;
-using System.Linq;
+using Newtonsoft.Json.Linq;
 
 namespace Microsoft.Azure.Management.ApiManagement.ArmTemplates.Extract
 {
@@ -786,7 +787,7 @@ public async Task<Template> GenerateAPIsARMTemplateAsync(string apimname, string
 
         private static void ArmEscapeSampleValueIfNecessary(OperationTemplateRepresentation operationTemplateRepresentation)
         {
-            if (!string.IsNullOrWhiteSpace(operationTemplateRepresentation.sample) && operationTemplateRepresentation.contentType == "application/json" && JToken.Parse(operationTemplateRepresentation.sample).Type == JTokenType.Array)
+            if (!string.IsNullOrWhiteSpace(operationTemplateRepresentation.sample) && operationTemplateRepresentation.contentType?.Contains("application/json", StringComparison.OrdinalIgnoreCase) == true && operationTemplateRepresentation.sample.TryParseJson(out JToken sampleAsJToken) && sampleAsJToken.Type == JTokenType.Array)
             {
                 operationTemplateRepresentation.sample = "[" + operationTemplateRepresentation.sample;
             }

src/APIM_ARMTemplate/apimtemplate/Extractor/Utilities/StringExtensions.cs

@@ -0,0 +1,24 @@
+using System;
+using Newtonsoft.Json.Linq;
+
+namespace apimtemplate.Extractor.Utilities
+{
+    static class StringExtensions
+    {
+        internal static bool TryParseJson(this string str, out JToken result)
+        {
+            try
+            {
+                result = JToken.Parse(str);
+                return true;
+            }
+            catch (Exception)
+            {
+                
+            }
+
+            result = null;
+            return false;
+        }
+    }
+}